Improvement in telephonic conductors



E. HOLMES 82 E. T. GREENPIELD.

Telephonio Conductor.

No. 221,170. Patented Nov. 4, I879.

11/21108 1B2 mm Zors:

N. PETERS, PMOTD-UTHOGRAPHER WASHMGTON, 0 CV UNITED STATES PATENT OFFICE,

EDYVIN HOLMES AND EDT VIN T. GREENFIELD, OF BROOKLYN, NE\V YORK.

IMPROVEMENT IN TELEPHONIG CONDUCTORS.

Specification forming part of Letters Patent No. 221,170,1lated November 4, 1879; application filed September 29, 1879,

To all whom it may concern: is carefully done, as with machinery, the con- Be it known that we, EDWIN HOLMES and struction will be uniform throughout, the EDWIN T. GREENFIELD, both of the city of nodes occurring at regular intervals, and the Brooklyn, in the State of New York, have incurves rising to uniform heights from the axial vented a new and useful lmrnovementinTeleline of the cable, which regularity of conphonic Conductors, of which the following is struct-ion will produce the most complete rea specification. sults.

The object of the present invention is to By braiding, again, each wire is made to act prevent or eliminate the effects of induction as a support to its neighbors, and while the in electric conductors that are arranged in wires thus serve to support each other the near proximity to each other, and which is whole cable can be as readily mounted on one of the principal disturbing influences in poles, or otherwise supported or submerged, the practical working of ordinary telephonic as a single wire can be. lines. Figure 1 shows a cable composed of three It is well known, scientifically, that the ininsulated wires braided together; but, manitensity of the induced currentdependslargcly festly, the same system would apply to any upon the parallelism between the conductor in larger number of wires, which, equally well, which such current is generated and the primight be braided up into a single cable. inary line, and that such current grows fee If two wires only were to be used they bleras the parallelism of thelines is destroyed, might be braided into a cable by using as a and becomes inappreciable when the lines third strand a cord of any non-conducting cross each other at right angles. material, or they might be secured by sewing,

It has been proposed to utilize for a teleor in any other available way, to a strip of phonic line a metallic circuit, the return-wire tape or any other suitable support, as shown of which shall be made to cross and recross in Fig. 2. In this figure two wires are shown repeatedly the main wire of the circuit, the as attached to a narrow strip in such a way as expectation being that such a line will not be to cross and recross each other at shortindisturbed by induction from a neighboring tervals and with regular curves. wire through which an electric current is pass- It is found in practice that when conductors ing. are arranged as above described no induced One practical objection to this construction current is formed in any one of them by the is that it requires double the length of wire passage of an electric current through any as compared with a construction which uses of the others, or, if formed it is so far modian earth-connection, and also is attended with tied from what it would otherwise be as praca vastly-iucreased resistance; moreover, it tically not to interfere with the working of proposes the protection of a single line only. any of the lines in the cable, and the same,

The present invention provides a simpler measurably, would be true of them with refand less expensive mode of utilizing the gencrencc to any other line near by, but not illeral fact above noted, and is perfectly adapted cluded in the same cable. to any number of lines arranged in proximity Vhat is claimed as new is to each other, and following the same gen- 1. The arrangement of two or more tele eral direction; and it consists simplyin weavphonic conductors with ground-connections, ing the lines in and out among themselves, so and so that each crosses and recrosses each that they will repeatedly cross and recross at and all of the others at short intervals, sub short intervals, each line having an carth-constantially as and for the purpose described. nection, and consequently no metallic return- 2. A cable composed of insulated telephonic wire. conductors having groundconnections and The most convenient way of securing this braided together, substantially as and for the relative arrangement of the wires is to braid purpose described. them together into a cab1e, for which purpose, EDVIN HOLMES of course, they must be piopeily insulated to FDWIW T GREEYFIELD prevent contact of the conducting-surfaces. L l By braiding them it will be caused that each Witnesses: one of the system will cross and recross each .SAML. A. DUNCAN, and every one of the others, and if the work ROBERT H. DUNCAN. 

